De Veritate Unicornis Modernus
by tepid sponge bath
Summary: John Watson, a unicorn of this day and age, is trapped in a mortal body. Life as it is seems pretty pointless, almost unendurable, until he meets one Sherlock Holmes, consulting detective and very much a virgin. As pointed out by I'm Nova on , the title should actually be De Veritate Unicornis Moderni. Do forgive my work-in-progress Latin!
1. Chapter 1

**Note**: Written for a prompt on the kink meme asking that John secretly be a unicorn, and Sherlock a virgin, with John being understandably protective/possessive. Not crack.

**Disclaimer: **The characters of _Sherlock _are not mine, nor is the story, nor are the characters from the original stories by Sir Arthur Conan Doyle. I make no monetary profit from this. I also acknowledge heavy borrowing from Peter S. Beagle's _The Last Unicorn_ and Michael Green's _De Historia et Veritate Unicornis_ and _The Book of the Dragontooth_.

**De Veritate Unicornis Modernus**

_**(On the Truth of the Modern Unicorn)**_

_Out of the hidden gulfs I made thee, free and by form unbounded. Wilt thou accept shape upon Earth, that thou mayst supply a service even greater?_ - The Unicornis Notebooks of Magnalucius

They were thought to have gone the way of the sphinx and the manticore, if they were thought of as having been real at all. They were not forgotten though, not like so many of the old gods, but then, also unlike the gods, their continued existence was not dependent on the sustained belief of human beings.

This, he knew, was a good thing. In the present day and age, all a unicorn was supposed to be was a horse with a horn.

It wouldn't have bothered him so much if it hadn't been horses, with their inelegant noise and heavy feet. He wouldn't have compared unicorns to any earthly animal at all, to be honest. The people who knew what they were talking about compared them to goats, to deer, to particularly graceful gazelles and antelopes, but even that fell dreadfully short of the mark.

Unicorns were unicorns, defined by - but so much more than - their possession of a single, spiral horn, and that was all there was to that. End of story.

Well, not really, not end of the entire story as such. Even unicorns had to change with the times, to learn to walk amongst concrete and steel and smog, to live with taxis and the Underground and aeroplanes.

He missed the old days of course, but he didn't find the present day strange. He had seen it grow up, so to speak, from the days of fire and the wheel, and so he was accustomed to the world as it was now, though every now and then he would come across a something new, an invention or some such thing, that would make him raise an eyebrow and wonder whatever mankind could _possibly_ think of next.

It was, however, getting harder to find people to choose and to cherish. This was their primary function, the purpose for which they had been created: to guide people to the right path, to stay in the light, to help them, in other words, to walk the straight and narrow. It could be argued that they ought to be there for the people who _needed_ saving, those who had fallen and needed more than a nudge in the right direction. And to this he would say, well, yes, but you needed to be pretty damn special to get a unicorn, just the _right_ kind of person, even if you had fallen a little ways, and there were other beings for those who were in need of a greater amount of salvation.

And being a virgin was still a prerequisite. So was a certain degree of innocence.

He hadn't had many charges in the twentieth century. The twenty-_first_ century had found him one Harriet - Harry - Watson, who had been beautiful and brilliant until she discovered women. And alcohol. She had cried when she realized that he was gone, and maybe that was when she started to truly come undone, and maybe it wasn't. But she had lost her unicorn, and he couldn't come back, not even to reproach her with his sad, ancient eyes.

The unicorn mourned the loss of his Harry and all that she could have been, in his way. Unicorns can sorrow, but they cannot regret, and he could only move on.

William Murray, Bill, had been found fairly quickly afterwards, which was practically a miracle in itself. He had some small magic of his own, an easy, open smile, and a constant sense of bewildered wonder at the fact that he merited a unicorn. He would reach out to touch the unicorn when it showed itself to him, his fingertips only just brushing the white coat, worshipful and just enough to confirm that _yes_ it was real. This flattered the unicorn, or pleased him, rather, to put a nicer word on it.

Bill had not expected the unicorn to follow him to Afghanistan. He had, in fact, tried to dissuade him from coming, certain that he would lose the unicorn there, one way or the other, and he didn't think he could bear it if he did. And the unicorn had told him that, bugger all, what kind of guardian did he think he was? He had walked with warriors before, and it was his job to keep Bill Murray safe. Mostly to keep him good, but safe was also a pretty high priority.

The unicorn wondered, much later, if it had been a near-terminal attack of hubris that had driven him then. He was, though immortal, much less than divine, and open to temptation. If unicorns had any sin at all in them, it was pride. Pride and vanity. For what greater feat was there than to keep a man innocent in the midst of battle? And who better to accomplish that than this one unicorn and his Bill Murray?

Things went well until they met the dragon.

It was on no-one's side. Bill's unit came across it in the desert one night, and it would have left them alone - for mankind does not need dragons to do evil, and it was content to live on the chaos and carnage of a pointless war - if it hadn't seen the unicorn.

The unicorn and the dragon are natural adversaries. There is nothing a dragon delights in more than the destruction of a unicorn, the dimming of a light placed by the Creator on the Earth.

Men died in the moment when the unicorn stood frozen in horror and disbelief. And more would have been killed if the dragon hadn't stopped to roar his triumph in a sound that shook the stars in the sky. (Dragons are also guilty of conceit.)

He charged as the dragon gloated, horn lowered, aiming for the monster's heart. Bill was still alive, and the unicorn was damned if he was going to let his charge die by dragon-fire.

The dragon lowered its head on its long, serpentine neck and locked its gaze on the figure galloping towards it across the sands. The eyes of the two creatures of legend met, and things began to look very bad for the unicorn. For one of his kind, there is no more deadly trap than to look into the eyes of a dragon and know darkness and despair.

The unicorn stood, unable to move, in front of the dragon, small and white, the brilliance of his horn lost in the smoke and flames of the beast's breath. He knew he was lost.

And then Bill Murray worked the greatest and last magic that he would do in his life.

There had been a real John H. Watson, Harry's brother, who had, by complete coincidence, been a friend of Bill's in the army. He had been an essentially good man who had done his quiet best, and, to be honest, the unicorn would have chosen to follow him rather than his sister if he hadn't lost his virginity and his innocence at fifteen (the girls liked John Watson, oh yes they had, and John Watson had liked them, _oh yes_).

He had died that night, burned out of existence by dragon-fire when he threw himself at the monster in an attempt to save his unit. A good man, a hero, if the unicorn had ever known one. And a complete life to step into.

Things could have been worse.


	2. Chapter 2

**De Veritate Unicornis Modernus**

Or maybe not.

The dragon lingered for a while, sniffing for its prey, the breath from its nostrils still hot enough to make the air shimmer even if it wasn't precisely flaming. Failing to find the unicorn and unaccustomedly confused, it spread its wings, immense starless shadows against the night sky, and took off.

It left behind a dark figure crumpled on the sand. The dragon's fire had caught the unicorn on the shoulder, but that was just a postscript to the real damage. He made a helpless sound. In another creature, or if he had known how to cry, it would have been a sob. The world was so _small_ now, and still shrinking.

"What have you done to me?" were his first words when he recognized who was running towards him by the light of the still-burning fires. (By sight, just by sight, _only_ by sight, _how_ was that possible when he would have known Bill Murray and exactly where he was if he had been put in a lead box and dropped in the middle of the sea?)

Bill stopped a respectful, regretful distance from what had used to be his unicorn. He held his hands away from his sides, stiffly, as though afraid of what they might do next.

"I'm sorry," said the self-confessed purveyor of small illusions and minor miracles. "I tried to work on the dragon, but it was too big. I couldn't. And. And I saw you, and-I was-I was only trying to help."

"Turn me back! For God's sake, _turn me back!_" screamed the unicorn thinly, through strange lips with unfamiliar lungs. He tried to get up and failed because he was coordinating a two-legged body with a four-legged mind.

There was a long moment when Bill stood, fiercely intent, all of his being concentrated on his unicorn. Nothing happened. He sagged and fell to his knees, utterly wretched. "I'm sorry. I don't know how. I'm sorry. I don't know how I did it. It was the first thing I could think of. It wanted a unicorn."

"You should have let the dragon take me then," said the unicorn bitterly, and it was a new feeling that twisted his mouth and tasted _wrong_. "You've robbed me of what I am. The dragon could only have killed me."

"I couldn't let it do that."

"You should have," said the unicorn again. "I can feel this body _dying_ around me. How can you _stand_ it?"

He began to cry then, and he thought he would die of it. Bill, helpless himself, placed what was meant to be a comforting hand on the unicorn's - what had been a unicorn's - undamaged shoulder.

It was the first time that he had touched, actually touched, the unicorn, beyond the little worshipful fingertip brushes. The weight and warmth of his fingers and palm confirmed, irrevocably, that the unicorn was no longer sacred and inviolate, which was much more jarring than merely being mortal.

It was the beginning of dark times.

Something broke inside Bill Murray that night as he held the unicorn while they waited to be rescued, careless of what the other survivors thought. He had taken something beautiful out of this world, had diminished and degraded a unicorn, his unicorn, and he didn't think he could live with that. He couldn't quite meet the unicorn's eyes anymore, afraid of seeing unicorn eyes in a human face, and even more afraid of _not_ seeing them, of knowing for certain that his unicorn was lost forever.

If the unicorn had been in his proper shape, he would have stopped following Bill at this point. He was still a good man, he would always be a good man, but some vital quality had been lost, fallen off into an abyss to be replaced by an unyielding despair like a cold ball of iron sitting above his heart. The unicorn felt some measure of guilt at having caused such a change, and he didn't know how he could make things better, wasn't sure that he could. But he looked at his human hands, flexed the fingers, felt the stiffness and pain in his human shoulder, and suddenly he wasn't altogether sure if he wanted to. (He would have just left before, simply gone away, because it wasn't his responsibility anymore, but walking away was harder when you needed a passport to cross borders.)

John Watson's shoulder was burned so badly that he was invalided home. (The story was that it had been some sort of bomb. It was how the human brain handled things. Even the other people who had been there had convinced themselves of the truth of this.) He was diagnosed with PTSD and given therapy for that and a psychosomatic limp.

Therapy did not work. Therapy was bullshit. It wasn't their fault, the unicorn thought, trying his best to be kind. They weren't treating him for having been attacked by a dragon and trapped in a human body, and if he had told them so, explained to them exactly what he was having a bloody hard time with, they would have locked him up for a lunatic.

Still, he was sometimes tempted to tell his therapist that no, it wasn't adjusting to _civilian_ life that would take some time. It was adjusting to mortal, _human_ life, so would she please shut the hell up and leave him be?

She was right about the limp being psychosomatic at least, if entirely wrong about the reason for it. If you had walked on four legs since the dawn of time, of course you'd limp if you hurt your shoulder that badly, and it was rather a hard habit to beat even if - _especially_ if - you found yourself suddenly bipedal.

Aside from when he was at therapy, John Watson (it was so strange having a name, he'd never needed a name before, simply being what he was had been enough) didn't talk much. He would sit in the small set of rooms that had been found for him, alone, listening to his heartbeat counting out the seconds of his life, quite unable to make himself do anything else. There didn't seem to be any point.

Bill kept in touch, tentatively, and, well, it was something to do, corresponding. They even met once in a while when he was sent home too, even if they hardly had anything to say to each other that wouldn't hurt, and had suddenly even less to say when Bill told the unicorn shyly, sheepishly that he was getting married. It was one of the nurses he'd met in Afghanistan. The unicorn had left then, had simply gotten up and limped away from the restaurant where they were having lunch. _I thought you were better than that_, he wanted to say to Bill, _I thought I was more important to you._

John - yes, he supposed he _was_ John now, with the name settling on him like a well-worn jumper - avoided Bill like the plague after that, which was easy. He had a harder job avoiding Harry, who was genuinely concerned for her brother's welfare, if unable to do sod all about it, what with being half-soaked in drink most of the time. He was terrified that she would be able to tell that it wasn't her brother who had come back to England, or, worse, that she'd be able to tell that it was the unicorn wearing his shape. He wasn't able to dodge her entirely, and she pressed her mobile phone on him one night, saying she didn't want it anymore. John was almost sure she knew then, when she looked him in the eye and told him, begged him, to keep in touch.

He never used the phone. And he didn't blog. He went on living, existing from day to bleak day, waiting for his body to die as it inevitably would (with or without the help of the gun - a unicorn with an illegally acquired gun imagine that, because putting himself out of his misery like some damned lame horse was so damnably tempting sometimes), impatient for it, in fact, until he met Sherlock Holmes.


	3. Chapter 3

**De Vertitate Unicornis Modernus**

It was an incredible chance, that meeting. The unicorn hadn't even meant to go to therapy that day, hadn't been in weeks really. And it was a minor miracle that he'd even paid any attention to Mike Stamford - he actually remembered that old classmate of the real John Watson's: he had attempted to pay suit to Harry back in the day – much less maintained civil conversation with the man, except for a growled "I'm not the John Watson you knew" when Mike had presumed to know where he'd rather spend the rest of his life. (It was remarkable, that – the unicorn didn't think he'd ever growled before.)

He doubted he'd ever be able to satisfactorily explain why he'd let himself be led to St. Bartholomew's Hospital to see a man about a flat. At the time, the unicorn put it down to the tedium, his new twisty impatience with the world that, he supposed, came from the knowledge that his body would only last a few more decades at best. (Boredom had never been a problem when he'd had the rest of eternity to look forward to. It had to be a mortal trait born, perhaps, from the stark reality that _you could be running out of time_.)

Whatever the reason, he'd somehow let it slip that if he was going to go on living, he couldn't afford to do it in London, not even living – such as it was – as he did, but he didn't want a flatmate, didn't want to share space with any poking, prying, living, breathing human being. Hell, he didn't even want to stay in London: there was too much _life_ in the city, and it hurt to be in a place like that, with all that _living_ going on just a wall's thickness away, when all you were doing was waiting to die. Yet there he was, climbing up stairs behind a wheezing Mike Stamford – yes, the man had gotten fat – to meet Sherlock Holmes.

Much later, when the unicorn no longer viewed everything with a crippling cynicism, he would wonder if providence hadn't deserted him after all, after the change. He'd met someone like Sherlock once, in the fourteenth century - the man wasn't entirely unique - but the resemblance ended at the pale eyes and the ability to tell entire life histories from fingernail clippings. The unicorn had wanted to kick the fourteenth century man's teeth in. But Sherlock Holmes…

He wasn't the sort of person the unicorn would have followed if he had been whole and entire. There were too many dark spaces inside his head, too many shadows; the man certainly had one of those Pasts with a capital P that nobody liked to talk about. And there was Pride, also with a capital P, but the unicorn understood pride. Pride, like being gay and working on a Sunday, was only a sin depending on who you talked to, and a modicum of it wasn't always a bad thing (otherwise, thought the unicorn, he'd be in trouble too, and would spend eternity in some quarter of Hell not described in Dante's Inferno – there was another man who'd known about pride – when he died). But there was no true evil in him. Just a tiny little germ of actual good, maybe, but nothing truly damnable. He was like a child, actually, a huge bundle of potential that could go either way.

He was also a virgin. Not, as far as the unicorn could tell (and to be honest, he was amazed that he still could tell at all), out of any particular desire to keep himself pure - it just seemed to be a genuine disinterest in sex.

It didn't matter. John Watson, erstwhile unicorn, was fascinated. He'd been hooked from the first question of "Afghanistan or Iraq?"

He blogged about the meeting that night, painstakingly writing his longest entry yet by poking at his laptop with two fingers (he hadn't gotten the hang of making his fingers fly over the keyboard, and he doubted he ever would). It was the first time he'd felt the need to articulate something, to put something into words so that he could look at the shape of it to understand things better. He'd never needed to do that in his proper shape - things just _were_ back then, unicorns didn't have internal struggles or identity crises or, for that matter, brilliant, life-changing revelations that they just _had_ to talk about.

It was also the first time since the change that he'd felt _alive_.


	4. Chapter 4

**Part Four**

_The dragon is a brooding spirit…He dissects everything with his cold and heartless mind. He worships beauty but comprehends it not._ – The Quest Notebooks of Magnalucius

That was nothing to what he felt the next day. The next day was a whirlwind, a hurricane of the first water that had the unicorn feeling as though he'd never really known what it was like to be properly alive in all his years. And if he'd had any doubts about wanting to follow Sherlock Holmes if he had to sleep on the pavement outside the man's front door, that following Sherlock Holmes was absolutely necessary to give his life shape and credence and meaning, well, he didn't have them any longer.

It was wonderfully hard to contain, hard to categorize, and that was why John blogged about it afterwards, when everything was all settled and Sherlock was doing something mysterious and unspeakable to a pair of eyeballs in the kitchen.

Not that it was all warm, clear certainty. Just a few minutes into their second meeting, the unicorn found out that Sherlock was far too happy about dead bodies for comfort, and it didn't help that it was the murdered ones in particular that floated his boat. Still, at least he wasn't in the business of _making _dead bodies, whatever that police sergeant thought, and what he did actually stopped other people from making more dead bodies, even if – and the unicorn would be a fool not to recognize this – it wasn't something Sherlock did purely out of the goodness of his heart.

And there was a moment of pure, heart-stopping terror when John Watson thought he'd lost Sherlock, when the man disappeared from the flat crowded with police officers, leaving a whiff of dragon-scent in his wake. Because John knew that a mind like Sherlock's – a clever mind, a brilliant one, fiercely logical and utterly rational, that weighed and measured and dissected everything it touched with a cold, vicious clarity– was that much more susceptible to dragon taint.

That is what dragons are like at their worst, even beyond being brutal and destructive and an utter menace to life and limb. Human minds, which are fully capable of being cunning and devious enough on their own, or even downright evil, can _twist_ under the influence of a dragon, and the result is never pretty. It's like a nasty communicable disease – dragon sickness, if you will – and it affects some people more than others, causing great and irreversible damage even at second or third-hand contact.

The unicorn's hopes came crashing down about his woefully inexpressive ears, and, if he'd been given to histrionics, he would have wailed at what the detective inspector said about great men and good ones. There was no way he could stay if that kind of damage was done, not even as he was, not even as just a flatmate. But, he reasoned, clinging to reason and logic as he never had before, it couldn't have happened that fast, not right under his nose without his noticing while he was _right there_, he was being stupid and jumpy just because he'd scented dragon, that was all, _that was all_, and that meant it wasn't Sherlock, not yet, but the man, who was infuriatingly refusing to answer his phone, was in danger, and lost to him in a city teeming with people.

And the computer, abandoned on the table ever since it started to say that the murdered woman's phone was at 221 Baker Street, began to blip.


	5. Chapter 5

**Part Five**

_And I am undone; for nothing had prepared me for the fiery touch of his wondrous mind. - _The Unicornis Notebooks of Magnalucius

John followed Sherlock, tracing the signal of Jennifer Wilson's phone on the computer (bless humans and their technology, bless them, _bless them_), shouting directions at a harried taxi driver and, over Harry's phone, at an astounded Lestrade (it was a good job that Sherlock had let him keep the D.I.'s ID he'd nicked). Five senses, luck, and GPS – it wasn't quite how he used to do things, but it would do.

Luck is a tenuous thing, though, and fickle. The unicorn could feel it slipping from him as he leapt from the cab, throwing a careless handful of notes at the driver, as ran up the stairs and down darkened corridors, peering into rooms where shapes were defined only by the faint street light seeping in through the windows. He was almost certain that he would be too late and find Sherlock dead or worse, and his heart gave a very human wrench between his very human lungs at the thought.

It was almost a relief when he found the man, but the relief died quickly because he was seeing Sherlock through the window, in the room directly opposite his, in the building that he _hadn't_ entered because it had been a fifty-fifty chance and his luck had turned sour at exactly the wrong moment. There was another man in the room with Sherlock – _his _Sherlock now, and so the unicorn claimed him – and John saw instantly that he was carrying the dragon-scent, the stuff wafting off of him like fifty kinds of crazy.

_Could be dangerous, _the consulting detective had said, and he couldn't have had any idea how dangerous things would turn out to be. In his own shape, his _old _shape, John Watson would have crashed through the windows, charging through the space between the buildings as though things like gravity didn't matter, to defend Sherlock with horn and hooves and a mind that had been old before the world was formed. But as it was, he was confused and lost and, yes, frightened, because the reek of dragon in his nostrils brought that night in Afghanistan back to life. He'd lost almost everything he knew that night, and he knew, as he called Sherlock in a futile attempt to get his attention, that he was inches away from losing more than everything now.

_Could be dangerous._ On the strength of that text, he'd brought his gun along, asking the ever so obliging woman in the black dress to make a detour on the way back to Baker Street so that he could pick it up, and he pulled it out now as Sherlock held a small white pill up to the light. The weapon felt strange in his hand, cold and grim and heavy, and he prayed as he had never needed to pray before that he would get things right.

The bullet went through two window panes and the cold night air, past Sherlock, and the way the other man dropped made it clear that it found its target. John didn't wait around to see the results of his handiwork. He'd killed before – the horn wasn't purely decorative and the point on it was very, very sharp – and always in defense of his charges, but he'd never been in a position where he'd have to answer for his actions. The law was going to be less than happy with him, he knew that much about modern police work, but he had done what he'd needed to do to keep his charge safe, and that was what mattered.

Yes, he was very loyal, very fast, just like the man with the brolly said, and, apparently, murderously protective in the bargain. It didn't bother him one bit – it was what he was made for, after all, and it was hard to shake the habit even if was wearing a different skin. And, going by the smooth way Sherlock took the matter in stride, how he diverted Lestrade's attention from him, and the infuriatingly smug way he asserted that he'd expected John to show up, it didn't seem to bother him either.

They walked away from the crime scene, laughing even after that, and went to get themselves a takeaway dinner from the Chinese place Sherlock had mentioned. Back at 221 B, the self-made consulting detective ate with chopsticks, skillfully wielding the things with his long fingers while John did his best with a fork. They talked until it was so late that the night was threatening to turn into morning, and it was so easy, so natural that John found himself asking the question that had been tickling the back of his throat ever since the lab at St. Bartholomew's.

"Do you know what I am?" he asked. It slid out on the lateness of the hour, and everything that had happened to them and between them that day, and maybe, just maybe, on a tiny hint of desperation. And Sherlock stared at him, a baffled look sitting uncomfortably on his face. The unicorn tried not to be disappointed. It was too much to ask, after all, even of this most brilliant of men. "No, never mi—"

"Unicorn. From the Latin _unicornis_, meaning 'one horn,' referring to a mythical horned beast, often said to resemble a horse, but I think that's a load of rubbish. And you are certainly older than the word." Sherlock's fingers brushed the barely-there bump on John Watson's forehead, which was all that remained of the horn his kind was named for, and he frowned a little, as if in consternation. "Of course I saw it. I don't know how you got like that, I don't know what you're doing here, but I saw it. Did you think I missed it?"

"Yeah, actually, I did." John Watson smiled. "Good to know I was wrong."

He spent the night on the sofa of 221B, and in the morning he moved in properly, ferrying his clothes, his laptop and the rest of his earthly possessions to Baker Street in a large, black taxi. It was an adventure such as he hadn't had for an age.

A flawed man and a damaged unicorn. John Watson figured that, for either of them, it could have been worse. And as far as he was concerned, it certainly couldn't get any better.


End file.
